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Across 2. muscles or glands that effect changes in the body 4. A gap in the myelin sheath of a nerve, between adjacent Schwann cells (3 Words) 5. electrically neutral subatomic particles 6. the difference in electrical charge between the inside and the outside of an undisturbed nerve cell membrane (2 Words) 7. Process of a neuron that receives input from other neurons 8. fatty layers formed from certain neuroglia that surrond axons, providing insulation (2 Words) 11. the sequence of electrical changes that occurs in a portion of a nerve cell membrane that is exposed to a stimulus that exceeds the membrane's threshold (2 Words) 12. motor pathways of the peripheral nervous system that lead to the skin and skeletal muscles (3 Words) 13. Any of the fibers in a mixed nerve that transmit motor impulses (2 Words) 14. portion of nerve cell that includes a cytoplasmic mass and a nucleus, and from which nerve fibers extend (2 Words) 16. a nerve fiber that carries impulses toward the central nervous system (2 Words) 17. chemicals that axons secrete on effectors ( muscles or glands) or other neurons 19. part of the nervous system outside the central nervous system (3 Words) 21. The delicate network of branched cells and fibers that supports the tissue of the central nervous system 22. a neuroglial cell that supports neurons and phagocytizes 23. Specialized structures associated with the peripheral ends of sensory neurons specific to detecting a particular sensation and triggering nerve impulses in response, which are transmitted to the central nervous system (2 Words) 25. the membrane potential to which a membrane must be depolarized to initiate an action potential (2 Words) 26. the functional connection between the axon of a neuron and the dendrite or cell body of another neuron or the membrane of another cell type

Down 1. the brain and spinal cord (3 Words) 3. neuroglial cells that line the ventricles of the brain (2 Words) 4. a bundle of axons in the peripheral nervous system 9. a type of neuroglial cell that connects neurons to blood vessels 10. part of the nervous system that controls the viscera (3 Words) 15. A type of neuroglial cell that foms myelin 18. masses of neuron cell bodies, usually outside the central nervous system 20. a type of neuroglial cell that surrinds an axon of a peripheral neuron, forming the neurilemmal sheath and myelin (2 Words) 24. a nerve fiber. it conducts a nerve impulse away from the neuron cell body